Along with the rapid growth in fixed diffractive and holographic element technology in recent years has come intensive interest in active, dynamic diffractive elements which can be electrically programmed or switched. Two different classes of electrically controllable diffractive structures may be distinguished. The more familiar class are the programmable spatial light modulators, addressed on a pixel-by-pixel basis. Less familiar is the emerging concept of monolithically switched holograms, now an active subject in several laboratories. These have a fixed, prefabricated diffractive structure whose diffraction efficiency can be modulated as a whole. Whereas spatial light modulators typically are restricted to relatively small arrays of pixels on the order of 256X256 and correspondingly low diffraction efficiencies, monolithic holograms can be of extremely high resolution, optical quality, and diffraction efficiency, with the equivalent of one million times higher pixel density. Such elements can yield new devices significantly different from SLMs, particularly if the material is also of sufficiently high optical quality to permit series stacking. Along these lines, Foster-Miller has been developing applications for a promising material, liquid crystal infused Polaroid holographic photopolymer, which appears to be a possible basis for many such devices. The present paper reviews some of our applications trials to date, including lab demonstrations of laser beam diverters, programmable beamlet array generators, dynamic lenses, fiber optic switches, both reconfigurable and continuously tunable wavelength filters, holographic optical memories and memory structures, and thermal applications for switching of white light or sunlight.